Manufacture of glassware.



H. C. FRY.

MANUPAGTURE 0F GLAsasvvuua,v

APPLICATION FILED HAY 7, i908.

Patented vMay 31,1910.

WITNESSESI HENRY C. FRY, 0F ROCHESTER, PENNSYLVANIA.

MANUFACTURE 0F GLASSWARE.

Specification of Letters Patent.

Application led Hay 7, 1908.

Patented May 31, 1910. serial No. 431,391.

To all whom 'it may concern:

Be it known that I, HENRY C. FRY, residing at Rochester, in the county of Beaver and State of Pennsylvania, a citizen of the United States, have invented or discovered certain new and useful Improvements in thev Manufacture of Glassware, of which improvements the following is a specification.

The invention relates to the finishing of the surfaces of glass articles, aud consists in a new and improved method which is particularl adapted to finishing the inner surfaces-ofy pressed glass articles, which are intended to be cut or otherwise dressed and polished on the outer surfaces, to produce ware of high Ofi-ade. lt is well known that in ressing glaass articles the plunger and die eave on t-he surface of the article imperfections, which must subsequently be coinpletely eradicated if an article of high grade is desired. The imperfections on the outer surface may be removed by mechanical polishing, but it is impracticable to polish the inner surfaces of many forms of articles by mechanical means. It is also known that if a pressed glass article be allowed to cool below a certain point, its surface will become set, and a glaze will be formed thereon which will render the imperfections perinanent, so that they cannot be. removed by any known method of lire-finishing. Hence in the manufacture of pressed glass articles intended to be cut or otherwise converted into ware'of superior finish and appearance, it has heretofore been necessary to remelt their inner surface before the article has lost so much of its initial heat as to permit the for-- mation of the glaze which renders the imperfections permanent. Said method of iinishin is described in Letters Patent of the United States No. 628,027, dated July 4th, 1899.

By the practice of the invention hereinafter described I am enabled to finish the surface of a pressed glass article, and eradicate all inold-marks and other imperfections, after the article has become cold, or after its temperature has been allowed to fall below thepoint at which the glaze above inen-y tioned has formed on its surface.

Any suitable apparatus may be emplo ed inthe practice of the invention, that il ustrated 1n the accompanying drawin s, and hereinafter described, bein mere y one form which is well adapted t ereto.

Figure 1 is a sectional elevation of the apparatus; Fig. 2 a cross-section on larger scale on the line II-II of Fig. l; and Fig. 3 a sectional lelevation of the remelting burners.

The numeral 1 yindicates a heating-furnace wen, provided with the chamber 2 which is heated by the burners 3, 3 arranged alternately on opposite sides of the furnace, and discharging into the flues 4, 4, passing through the crown of the furnace and connect-ed by the longitudinal passages 5, 5 to the stack.

The numeral tS-indicates the entrance o ening to the chamber, provided with the oor 7, and 8 the delivery opening, provided with the door 9, The heating flues are so arranged, as shown on Fig. 1, that the glass articles in passing through the furnace are subjected to a gradually increasing temperature, so that they are gradually heated to a temperature above that at which the glaze above mentioned had originally formed on their surface. It is preferable that the glass articles should be heated gradually, since if they were exposed at once to a high temperature they would be in danger of being cracked or broken.

During their passage vthrough the furnace the glass articles should be supported in matrices which fit closely upon their eXteiior, in order to guard against distortion. For this purpose I have shown the articles contained in the open supports 10, which may be made of any suitable material, such as iron, and may if desired be'coated with asbestos or other refractory substance.

I have shown the supports 10 mounted on Wheels running on ways 11, which rest upon the floor of the chamber 2, and for causing them to move through the chamber an endless chain 12, provided at proper intervals with dogs 13, adapted to enga e depending pieces 14 on the supports 10. he chain 12 passes over wheels 15 arranged at the opposite ends of Ithe furnace, and may be operated by any suitable means. sira'ble ipes 16 may be arranged along the Hoor ofp the chamber, provided with perforations through which cold air may beprojected against the bottoms of the supports 10 to prevent their becoming so highly heated that the glass articles will stick to their inner surfaces.

Adjacent to the delivery end of the fur- If found denace are mounted the remelting burners 17. Each of these burners is shown as provided with a combustion chamber 18, lined with refractory material,and opening downwardly so as to direct the flame within a glass article laced beneath it, and remelt the inner sur ace of the article. Gaseous fuel is' suplied to the combustion chamber of each burner from the nozzles 19. One or more remelting burners may be used, as found desirable, and arranged in any convenient way.

It is essential that the glass articles while exposed to the remelting flame shall be supported on their exterior walls, so as to prevent distortion, either by the supports 10 or by other suitable means.

In the practice of the inventionwith the a paratus described, the glass articles are p aced in the supports 10 and are transported therein through the chamber 2 at such speed as will allow them to be gradually elevated in temperature to a point above that at which the laze above mentioned had originally former? upon the surface to be finished. The degree of temperature of the formation of sai glaze, and consequently the degree of temperature to which the articles must be reheated, yvaries according to the composition of the glass, and is Well understood byv those skilled in the art. When the articles have attained the desired temperature, and have reached the delivery end of the furnace, they are Withdrawn from the chamber, and while still at a temperature above that of formation of the glaze, the surface to be finished is exposed to the flame of the remelting burner, by means of which said surface is thoroughly remelted, and all mold-marks and other surface imperfections are completely eradicated. 4The article Y, /is

' then allowed to cool, and is annealed in the usual manner. y

Within the sco e of the invention, the glass article may e gradually -reheated in an suitable furnace or oven, 'or by any suitab e means, and the surface to be finished, when raised to the proper temperature, may be remelted by any suitable means, it being only necessary that the article shall be gradually heated to a temperature above that of the formation of the glaze which prevents the removal of surface imperfections by relinishing, and while still above said degree of temperature, the surface to be finished shall be remelted.

I claim as my invention:

1. The method of finishing the surfaces of glass articles, which consists in gradually heating the surface to be finished to a degree of temperature above that of formation of the laze, and then remelting the surface.

2. T e method of finishing the surfacesof glass articles, which consists in gradually heatin the article to a degree of temperature a ve that of formation of the laze, and then remelting the surface to be finlshed.

3. The method of finishing the surfaces of glass articles, which consists in gradually heating the article to a degree o temperature above that of formation of the glaze, and then remelti the surface to be finished, maintaining the s ape of the article throughout the operation, and then allowing the article to cool.

In testimony whereof, I have hereunto set my hand.

HENRY C. FRY. Witnesses:

CHARLES BARNE'rr, J. HERBERT BRADLEY. 

